Anatomical Distribution of Intramuscular Lipomas

Abstract

EDITORIALLipomas are the most common type of soft tissue tumor occurring in the subcutaneous tissue. Rarely, lipomas present in the deep soft tissue such as intermuscular, intramuscular, and parosteal sites. When they occur within a skeletal muscle they are called intramuscular lipomas. Intramuscular lipomas may involve both children and adults. They are benign, nontender, deep located, circumscribed but unencapsulated lesions. Intramuscular lipomas account less than 1% of all lipomas. Most are located within a single muscle (solitary), while cases involving two or more muscles are very rare. They present with typical histological features. They may be divided into the in iltrative, the well-circumscribed and the mixed type. Differential diagnosis of the in iltrative type from liposarcoma is very dif icult. Local recurrence may be evident if the surgical margin is not clear. They can occur in almost any anatomical site [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15].Intramuscular lipomas of the head may involve the tongue, which is one of the most commonly involved sites [16][17][18][19][20][21][22][23][24] The chest wall [44,45] and the intercostal muscles [46] may also be involved. It may appear as a breast mass involving the pectoralis major [47][48][49] and may also involve the heart; involvement of the left ventricular myocardium, extending to the epicardial space; has also been reported [50]. The large muscles of the trunk may be involved such as the trapezius, the latissimus dorsi, the rhomboid major and the muscles of the anterior abdominal wall [14,51].